When I built my Roar of the Pelican, a Maglight 2D flashlight modified to be really bright, I used two cheap 3AA to 1D adapters. I needed 6 AA NiMH batteries to make 7.2 V to power the bi-pin incandescent bulb.
I’d read warnings about some cheap battery adapters not being able to handle the high current, so I bought the beautifully engineered Fivemega 6AA to 2D adapter.
The negative end of the adapter fits inside the spring in the Maglite tail cap. The adapter also has a charging jack that takes a 5 mm coaxial DC power plug, so the pack doesn’t have to be disassembled to charge the batteries. Besides 6AA to 2D adapter, Fivemega makes a 9AA to 3D adapter and 3AA to 1D adapter, among other flashaholic things.
This Candlepowerforums thread has some links but they’re old. Also eBay has some.
Also looking for the 2D and 4D adapters.. where do u get them.
Where did you get the battery adapter